Background and ObjectiveFire is a significant ecological factor that influences rangeland ecosystems, particularly in arid and semi-arid regions, where it plays a crucial role in the growth, development, and evolution of plant species. Historically, controlled burning of vegetation in natural ecosystems has been one of the simplest methods for altering and enhancing habitats, as well as for eliminating pests, diseases, and undesirable plants, while also modifying vegetation cover. Understanding the effects of fire on the characteristics of rangeland vegetation is essential for effective post-fire management. Therefore, this study aims to investigate the impact of fire on specific vegetation characteristics and to analyze vegetation responses to fire, with the goal of improving the management of the Sanandaj rangelands. MethodologyFor this study, three areas Khalichian, Hasanabad, and Haft Asiab located around Sanandaj and affected by fires one to three years prior were selected. Following field surveys and sampling, the flora of these areas was identified using available resources. Vegetation types were determined through the physiognomic-floristic method. Six sites were established for vegetation sampling, comprising three burned sites and three control sites. Each pair of burned and control sites was matched based on topographic conditions, including elevation, slope percentage, and slope direction, to minimize the effects of environmental gradients and focus on the impact of fire. In each site, two transects (one along the slope and one perpendicular to it) were established, with 15 plots along each transect, resulting in a total of 12 transects and 180 plots. Within each plot, vegetation characteristics such as the percentage of canopy cover of plant species, bare soil, stones and gravel, and litter were estimated. The Shannon-Wiener index was utilized to calculate diversity and evenness, while the Margalef index was used to assess richness. An independent t-test was conducted to compare the mean vegetation characteristics. ResultsThe results revealed a significant decrease in the canopy cover of shrubs in the burned sites, accompanied by notable increases in the cover of grasses and both annual and perennial forb plants. Total canopy cover, bare soil percentage, production, and species richness significantly increased in all three areas as a result of fire, while litter significantly decreased. Total rangeland production in the fire-affected sites was significantly higher than in the control sites (P < 0.01), with increases of 26.48%, 26.48%, and 40.14% observed in Khalichian, Hasanabad, and Haft-Asiab, respectively. The difference in the species diversity index (Shannon-Wiener index) was not significant in Khalichian; however, it showed a significant increase in the other areas. Comparisons of the Margalef species richness index indicated that fire enhanced species richness in all three areas, with increases reaching significance at the 1% level. The species evenness index exhibited a significant increase in Hasanabad and Haft-Asiab, but not in Khalichian. An examination of plant composition in the studied areas indicated that fire reduced the prevalence of woody species while promoting an increase in herbaceous plants. ConclusionThis study concluded that fire generally results in an increase in live vegetation cover, a reduction in litter, and an increase in bare soil. Additionally, fire alters plant composition, favoring herbaceous plants over woody species. Therefore, it is recommended that controlled burning be implemented in grasslands where plant composition has shifted and woody species have proliferated. Such practices should be considered alongside other economic, social, and environmental factors to enhance rangeland conditions.

Background and ObjectivesFlood spreading has emerged as one of the most important management strategies for soil and water resources in arid and semi-arid areas, gaining attention from researchers worldwide in recent decades. This technique has been implemented in various watersheds globally to address the critical issue of moisture scarcity, which is a significant factor limiting plant growth in these regions. The flood spreading system not only supplies moisture for plants but also helps recharge underground aquifers, making it one of the most innovative methods developed for water management in arid and semi-arid environments. By effectively utilizing floodwaters that would otherwise be lost, flood spreading offers a viable solution for enhancing water resources and supporting sustainable agricultural practices in these challenging landscapes. MethodologyIn this study, we investigated vegetation density, regeneration, trends, and the condition of rangelands at the Abbarik Bam flood spreading station. To assess the effect of flood spreading on vegetation cover, we identified the site with the most flooding, located away from tree cover, and established four transects, each 100 meters long and spaced 15 meters apart, parallel to the distribution channels. Ten plots were installed along each transect, with a distance of 10 meters between them. At the end of the one-year period, we compared the collected data to accurately assess the changes in the flood spreading environment relative to a control environment, both of which were selected for grazing exclusion. This comparison allowed for an informed evaluation of the effects of flood spreading on vegetation density in the area. The experiment was conducted using a split-plot design in a randomized complete block format with four replications. The main plots included flooded, non-flooded, and control areas, while the subplots encompassed five vegetative forms: perennial grasses, perennial forbs, annual grasses, annual forbs, and density parameters were recorded. ResultsThe results also revealed that the density of forb plants was 2.6 times higher in flood-free plots and 4.2 times higher in flooded plots compared to the control area. In contrast, the density of perennial grasses was 0.1 times lower in flood-free plots and 0.05 times lower in flooded plots than the control area. The density of perennial broadleaf plants was 1.7 times higher in both flood-free and flooded plots compared to the control area. Interestingly, the density of annual grasses was 30.78 times higher in flood-free plots and 6.3 times higher in flooded plots than the control area. Finally, the density of annual broadleaf plants was 2.4 times higher in flood-free plots and 5.1 times higher in flooded plots compared to the control area. ConclusionThe results indicated that the highest average vegetation density in flood-free plots was associated with the annual grasses, followed closely by annual broadleaf plants. In the control plots, the highest average vegetation density was found in annual broadleaf plants, followed by perennial grasses. Additionally, the impact of vegetative form on vegetation density was greatest for annual wheat and annual broadleaf plants, while shrub plants exhibited the lowest density. Therefore, the observed differences in vegetation cover between flooded and flood-free areas in the study region may be attributed to factors such as moisture content, nutrient availability, the accumulation of fine-grained sediments, root and bud choking, and reduced soil permeability.